Adsorption and enhanced photocatalytic activity of the {0 0 0 1} faceted Sm-doped ZnIn2S4 microspheres

Rapid adsorption and photocatalytic activity for Rhodamine B and Cr(vi) by ultrathin BiOI nanosheets with highly exposed {001} facets

“…To study the contribution of the S BET of the 20 prepared samples on their adsorptive capacity or photocatalytic efficiency, the specific BET surface areas (S BET ) and pore structure of the samples were investigated by nitrogen adsorption and desorption isotherms. The 30 corresponding pore size distribution of the sample is shown in the inset of Figure 5, which confirms that it contains larger mesopores with a broad distribution in the range of 20-120 nm. The surface area (S BET ) of the BiOI microspheres was calculated to be 77.22 m 2 /g, which is about three even four times larger than other reported [33,34].…”

“…20 In order to better understand the microstructure of the BiOI nanostructures, TEM, selective-area electron diffraction (SAED) and HRTEM were carried out and the results are shown in Figure 3. The HRTEM images in Figure 3d clearly exhibit the lattice interval of 0.281 nm and 0.280 nm, which corresponding well to that of the (110) and lattice planes of the tetragonal phase BiOI respectively, thus can indicate the BiOI nanostructures are well with exposed highly reactive {001} 30 facets [29][30][31]. The HRTEM images in Figure 3d clearly exhibit the lattice interval of 0.281 nm and 0.280 nm, which corresponding well to that of the (110) and lattice planes of the tetragonal phase BiOI respectively, thus can indicate the BiOI nanostructures are well with exposed highly reactive {001} 30 facets [29][30][31].…”

“…Obviously, the adsorption equilibrium was also established during the first 4 minutes, which 10 can confirm that the adsorption processes were also very fast. Nevertheless, considering the exposed surface with the dominant negative {001} facets, most reported papers about Bismuth oxyhalides were found to demonstrate high adsorption for cationic dyes, whereas undesirable for anionic ones [30,31]. Obviously, Cr(VI) exists in forms 20 of anion during the adsorption process.…”

“…25 Therefore, many technologies have been applied to remove the pollution from the wastewater, such as sedimentation [3], biological treatment [4], ion-exchange [5], adsorption [6], photochemical oxidation [7], membrane processes [8], and photocatalytic degradation [9,10]. Among them, the adsorption 30 and photocatalytic degradation exhibit high efficiency, low costs, and simple operation process for removing the contaminants in wastewater [11,12]. Thus, it is imperative to explore a novel kinds of materials with both adsorption and photocatalytic degradation properties for the commendable treatment of 35 wastewater.…”

“…For instance, the facet effect of anatase TiO 2 on its photocatalytic activity was extensively researched and found that the {001} facet is an active facet due to having more under-coordinated Ti5c centers and higher specific energy [24][25][26]. According to Wang et [29][30][31]. Therefore, BiOI nanostructures with the dominant negative {001} facets exposed should be with interesting adsorption property and photocatalytic activity for the pollutant under visible light irradiation.…”